In a mobile communication system, the speed of user equipment influences the quality of the services provided by a network, especially in the processing of cell reselection or handover, if user equipment in a high-speed motion adopts controlling parameters for a normal motion, there is a possibility that the user equipment is out of the coverage of a serving cell before the user equipment reselects or is handed over to a target cell. Thus, in the current mobile communication systems, cell reselection or handover is executed according to the controlling parameters which are dependent on a mobility state of user equipment, that is, a motion speed.
Two evaluation parameters are defined in existing mobile communication systems: T and N. T is a timer used in mobility state evaluation of user equipment, and N is a preset threshold value. In mobility state evaluation, user equipment counts the times of executing the cell reselection or handover within a time period of T, the user equipment is deemed to be in a high-speed mobility state if the counted times exceeds N times, otherwise, the user equipment is deemed to be in a normal mobility state.
However, if the user equipment enters a cell with different evaluation parameters during the process of evaluation, according to existing protocols in which evaluation parameters are broadcasted in cell system messages, the user equipment will inevitably read the new broadcast message when entering the cell and update the parameters stored in the user equipment. As the parameters different from the previous ones are obtained, the user equipment cannot determine which group of parameters should be used in the following state evaluation, and consequently confusion is caused in execution.